System, apparatus and method for contaminant reduction in semiconductor device fabrication equipment components
A system, apparatus, and method for reducing contaminants of semiconductor device fabrication equipment components, featuring a manifold having a passageway in fluid communication with to a plurality of inlets and for providing a purge fluid to removably connected components to undergo contaminant reduction. The inlets are connected to a plurality of manifold valves to which components are removably connected. The manifold valves are operable to place connected components into and out of fluid communication with the inlets and the passageway. A fluid source supplies purge fluid to the manifold and a pump is connected to the manifold to remove fluid from the system. In one embodiment an oven is connected to the system for outgassing and for reduction of moisture in additional components.
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The invention relates to semiconductor device fabrication equipment in general, and, in particular, to a system, apparatus, and method for contaminant reduction of semiconductor device fabrication equipment components.
BACKGROUND OF THE INVENTIONSemiconductor device fabrication equipment components tend to accumulate contaminants, through for example, adsorption and absorption, before, during, and/or after the operation of the fabrication equipment. Such contaminants include, for example, moisture, oxygen, atmosphere, or any other gases. Possible contaminant sources are process gases as well as the atmosphere. Even components that have been cleaned, by cleaning processes known in the art, or that are new, are subject to accumulation of contaminants. Thus, the components of the semiconductor device fabrication equipment become a source of contaminants, in addition to process gases. Contaminants on components are undesirable for at least the reasons that they degrade the quality of the fabricated semiconductor device manufactured and reduce the efficiency of the fabrication process.
Where the method of semiconductor device fabrication involves depositing epitaxially-grown silicon germanium (SiGe) on a silicon substrate in a chemical vapor deposition (CVD) reactor, during SiGe deposition, oxygen present in the CVD reactor is typically incorporated into the SiGe film. Elevated oxygen levels present in the CVD reaction chamber used to deposit SiGe causes numerous problems in the SiGe films produced in the CVD reactor chamber. Among these problems are elevated sheet resistance of the SiGe p-type base and poor crystal quality.
Additionally, as the amount of absorbed or adsorbed contaminants, such as oxygen, increases, the amount of time for which the reactor must be taken offline typically increases in order to achieve acceptable oxygen levels in SiGe films. While the reactor is offline, it is disassembled to remove contaminants, reassembled, and then tested. The longer the reactor is offline, the less cost effective manufacturing becomes, as an offline reactor cannot be used for manufacturing semiconductor chips.
Also, elevated contaminant levels in the reactor components may lead to early reactor failure and a decreased reactor lifetime.
Therefore, it is an object of the present invention to provide a system, method, and apparatus for reduction or elimination of contaminants found in semiconductor device fabrication equipment components.
It is another object of the present invention to reduce or eliminate levels of contaminants on semiconductor device fabrication equipment components.
It is a further object of the present invention to improve the quality of semiconductor devices manufactured with semiconductor device fabrication equipment.
Additional objects of the present invention are to reduce preventative maintenance recovery time, process recovery time, and mean time to repair (MTTR) and to increase mean time between interrupt (MTBI) and mean time between cleans (MTBC).
SUMMARY OF THE INVENTIONThe above and other objects have been met with a method, system, and apparatus each of which, in one exemplary embodiment, feature a manifold which associates a plurality of components together so that they may be selectively placed into and out of fluid communication with fluid, such as a purge fluid, introduced into a main passageway for reducing the amount of contaminants present on surfaces of the components. The purge fluid may include a gas selected from a variety of different types of gases, including nitrogen. The purge fluid may be inert. The manifold has a pair of capped ends, a main passageway, a plurality of inlets in fluid communication with the main passageway, manifold valves connected to the plurality of inlets to which semiconductor device fabrication equipment components are connectable, and an exhaust fitting connected to the manifold at a location downstream from the inlet closest to the capped end. In the system, one of the capped ends is connected to a fluid source and the exhaust fitting is connected to a pump which pumps fluid introduced into the manifold out of the manifold under vacuum. The term vacuum, as referred to in the description of the present invention, means a low pressure environment.
In one embodiment, the system and apparatus further include caps which are connectable to the manifold valves and to a type of component to undergo contaminant reduction having a pair of openings. When a component having two openings, such as a ball valve or a pressure control valve, is connected to a manifold valve for contaminant reduction, one end of the component is connected to the manifold valve at an end having a first opening and the other end of the component having a second opening is capped with a cap to maintain the vacuum within the manifold by preventing atmospheric particles from entering the component and manifold. When the component is a rotation assembly, one end of the rotation assembly including an opening is connected to the manifold valve, while the other end is typically already closed and thus does not require a cap. When a component is not connected to a particular manifold valve, an uncovered manifold valve opening may be capped to maintain the vacuum within the system when the valve is in an open position.
Cap valves may be connected to the caps. When the manifold is in use, a vacuum typically exists within the system. When components are to be removed from the manifold, the cap valve is opened to slowly let air into the component and to vent the component out to atmosphere.
In another embodiment, the system includes an oven connected to the pump for outgassing components of semiconductor device fabrication equipment.
In operation, a purge fluid, such as nitrogen gas, is introduced into the manifold. Nitrogen gas, in particular nitrogen gas introduced in a vacuum, assists in the removal of oxygen from surfaces of the components. Components to undergo contaminant reduction are connected to the manifold valves. In one example, three sets of components (each set including, for example, two of the same type of component and each component having at least one opening) are connected to the manifold valves at the openings. For instance, two rotation assemblies, two ball valves, and two pressure control valves are connected to manifold valves of the system. The inlets of the manifold may be facing downwardly for connection to a manifold valve to which a rotation assembly is to be connected, or frontwardly for connection to a manifold valve to which a ball valve or pressure control valve is to be connected. As stated above, the manifold valves and components may be capped to maintain the vacuum within the system. Fluid is introduced into the main passageway of the manifold and is dispersed to inner surfaces of components via the manifold inlets and connected manifold valves which are in the open position. Fluid is pumped out of the components, inlets, and manifold valves through the exhaust pipe connected to the pump. While the components are undergoing contaminant reduction, additional components may be disposed within the oven for outgassing. When the components have undergone contaminant reduction, they are removed from the system and are ready for use.
The apparatus and system of the present invention is advantageous in at least that it reduces the amount of contaminants, such as oxygen, found on surfaces of semiconductor device fabrication equipment components. A reduction in oxygen within the components will result in an improvement in the quality of semiconductor devices manufactured by the equipment.
Furthermore, the present invention may reduce contaminants of more than one component and more than one type of component at a time. These components may be connected to the manifold valves, found within the oven, or both.
Additionally, reduction of contaminants on components, with the system, apparatus, and method of the present invention, makes future removal of contaminants easier to achieve. Therefore, preventative maintenance recovery time, process recovery time, and mean time to repair (MTTR) are reduced. Further, mean time between interrupt (MTBI) of operation and mean time between cleans (MTBC) will increase as the semiconductor fabrication device equipment will not need to be maintained as often if contaminant reduction has been achieved with the present invention.
The system and apparatus of the present invention may be utilized in conjunction with semiconductor device fabrication equipment components for several different types of semiconductor processes including, for example, SiGe, EPI, thin film, diffusion, etch, and implant processes.
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In one embodiment, the system includes an oven 46 connected to the pump 32 via pipe 47. The oven 46 is, for example, a vacuum drying and outgassing oven. One example of the oven is manufactured by Oven Technology Incorporated (Albuquerque, N. Mex.). The oven 46 includes handle 48 for opening oven door 50 to the oven chamber (not shown). The oven also includes a controller, not shown here. Semiconductor fabrication equipment components, such as o-rings and internal chamber components comprising quartz, stainless steel, or silicon carbide (not shown), are placed within the chamber of the oven for drying and outgassing. The oven 46 is connected to pump 32 via pipe 47 which, in turn, is connected to pipe 34. Pipe 47 includes valve 43 for placing the oven into and out of fluid communication with the pump 32. The oven is supported by base elements 54 forming a part of a frame 56 (
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The type of component connected to each inlet may vary. The spacing between inlets should be sufficient to accommodate the desired components. Inlets may be downwardly facing, as are inlets 22a and 22b, or frontwardly facing as are inlets 22c–22g. The spacing and orientation of the inlets 22 assists in the accommodation of one or more sets of components.
One or more components or various sets of components from semiconductor device fabrication equipment may undergo contaminant reduction at a single time. In the example of
Additional semiconductor device fabrication equipment components having a surface, for example an internal surface, and at least one opening leading to the surface may be connected to the manifold valves to undergo contaminant reduction. The term surface may be used to encompass any surface of the component to undergo contaminant reduction.
Inlet 22a is spaced apart from flange 26a by, for example, 11.7 cm (4⅝ inches) from a center point of the inlet. Inlet 22g is spaced apart by, for example, 26.7 cm (10½ inches) from the flange 26b, measured from a center point of the inlet. Exhaust fitting 24 is spaced apart by, for example 9.68 cm (3 13/16 inches) from flange 26b, measured from a center point of the fitting.
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The second opening 126 of pressure control valve 84b is closed during operation of the system to prevent fluid, such as atmospheric particles, from entering the system and to allow the system to operate under vacuum. Specifically, cap 134b of cap assembly 135b closes opening 126 (
Chamber ball valves 86a and 86b, which are depicted in representational form, are connected to manifold 12 via manifold valves 30e and 30f, respectively (
The second opening 128 of chamber ball valve 86a is closed during operation of the system to prevent fluids from escaping the system and to allow the system to operate under vacuum. Specifically, cap 134c of cap assembly 135c closes opening 128 during operation of the system. Cap 134c includes a flange 132, which forms a flange connection 153 (
Referring to
Where a manifold valve lacks a connected component, as with manifold valve 30g, a cap such as cap 134e, may be used to seal an opening of the manifold valve. A cap is not required to seal an opening of the manifold valve 30g, as the valve 30g may be placed in a closed position by adjustment with handle 39g (
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The system operates under a vacuum. In one example, the manifold pressure is 25±5 Torr (0.5±0.1 psia) and the manifold flow rate is 20±2 slm (42±4 scfh). A variety of manifold pressures and flow rates may be used, however, low pressures are typically desired.
The manifold valves 30a–30g of the system operate independently of each other to place connected components, such as components 82, 84 and 86, into and out of fluid communication with the manifold 12. Therefore, an advantage of the system of the present invention is that one component may be removed without shutting down the entire system 10. Specifically, the manifold valve 30 connected to the component to be removed may be closed such that the component is no longer in fluid communication with the connected inlet 22. The component may then be removed from the system and utilized for semiconductor device manufacturing without disrupting the vacuum.
Further, because a plurality of components may undergo contaminant reduction by the system 10 of the present invention, a set of components from, for example, one reaction chamber, may be removed after contaminant reduction while another set from another chamber, for example, are still undergoing contaminant reduction. Additionally, replacement components may be connected to the manifold 12 to replace the removed set. In this manner, components belonging to semiconductor device manufacturing equipment may efficiently undergo contaminant reduction.
When the system is in use, a vacuum environment typically exists within the system, including the manifold 12 and the connected components. Therefore, before a component is removed from the system, it is desirable that the component is slowly vented out to atmosphere. Valves connected to the rotation assemblies are opened slowly to vent out the components to atmosphere before removal. For example, valve 122, connected to rotation assembly 82a via fitting 120 (
While the connected components are undergoing contaminant reduction, additional components, such as o-rings, may be disposed within the oven 46 for moisture reduction and outgassing. In one example, the oven is set at 65° C. and has an oven pressure of 25±5 Torr (0.5±0.1 psia). In one example, the oven flow rate is 14.1±4.7 slm (30±10 scfh). The temperature and pressure may vary.
When the components have undergone contaminant reduction, they are removed from the system and are ready for use. In one example, the components are connected to the manifold until it is time for use. Components undergoing contaminant reduction in the system of the present invention, in one example, remain under vacuum and exposed to the purge fluid for 30–35 days. In another example, the components are stored in, for example, a nitrogen environment until it is time for use. The amount of time for which the components undergo contaminant reduction may vary.
Although certain embodiments have been described for illustration, a skilled artisan will recognize various means for accomplishing a similar purpose. For example, valve handles 39 imply manual control means for connecting components to manifold 12. However, automated, computer and state machine-controlled valve control is considered to be within a scope of the present invention. Therefore, the scope shall only be determined by way of the appended claims.
Claims
1. A system for contaminant reduction of semiconductor device fabrication equipment components, comprising:
- a manifold having a main passageway with first and second capped ends, said first capped end configured to accept a purge fluid, a plurality of inlets disposed in between said capped ends in fluid communication with said main passageway, and an exhaust fitting disposed downstream from said plurality of inlets and being in fluid communication with said main passageway;
- a plurality of manifold valves, each manifold valve having a first end connected to one of said plurality of inlets and a second end to which a semiconductor device fabrication equipment component having a contaminated surface for contaminant reduction and at least one opening is removably connectable at said at least one opening, and each manifold valve being operable to place one of said plurality of inlets into and out of fluid communication with said surface of said removably connectable component;
- a purge fluid source; and
- a pump.
2. The system of claim 1 wherein said plurality of inlets are spaced apart such that two sets of components are connectable to said manifold valves, each set including at least two different types of components.
3. The system of claim 1 further comprising a plurality of caps, each of said caps removably connectable to said second end of said manifold valves and to components having two openings.
4. The system of claim 3 wherein one of said caps is connected to one end of one of said components when another end of said one of said components is connected to one of said manifold valves.
5. The system of claim 3 wherein one of said caps is connected to said second end of one of said manifold valves in the absence of one of said components connected to said one of said manifold valves.
6. The system of claim 3 wherein one of said caps forms a flange connection with one of said components when connected to said one of said components, and a flange connection with one of said manifold valves when connected to said second end of said one of said manifold valves.
7. The system of claim 3 wherein each of said plurality of caps is connected to a cap valve.
8. The system of claim 7 wherein each of said plurality of caps is connected to said cap valve via tubing.
9. The system of claim 1 wherein at least one of said inlets is a downwardly facing inlet.
10. The system of claim 1 wherein at least one of said inlet is a frontwardly facing inlet.
11. The system of claim 1 wherein one of said components is a rotation assembly.
12. The system of claim 11 wherein said rotation assembly is connected to one of said manifold valves with a ball joint.
13. The system of claim 12 wherein said ball joint includes a ball flange, a male connector, and a flange.
14. The system of claim 11 wherein said rotation assembly is connected to one of said manifold valves with a rotatable joint.
15. The system of claim 11 wherein one of said inlets is downwardly facing and said rotation assembly is connected to said downwardly facing inlet.
16. The system of claim 1 wherein said one of said components is a chamber ball valve.
17. The system of claim 16 wherein said chamber ball valve is connected to one of said manifold valves with a flange connection.
18. The system of claim 17 wherein said flange connection is a KF40 flange joint.
19. The system of claim 16 wherein one of said inlets is frontwardly facing and said ball valve is connected to said frontwardly facing inlet.
20. The system of claim 1 wherein one of said components is a pressure control valve.
21. The system of claim 20 wherein said pressure control valve is connected to one of said manifold valves with a flange connection.
22. The system of claim 21 wherein said flange connection is a KF40 flange joint.
23. The system of claim 20 wherein one of said inlets is frontwardly facing and said pressure control valve is connected to said frontwardly facing inlet.
24. The system according to claim 1 wherein said inlets include two downwardly facing inlets and four frontwardly facing inlets.
25. The system according to claim 24 wherein said components include a pair of rotation assemblies connected to a first pair of manifold valves which are connected to said two downwardly facing inlets, a pair of pressure control valves connected to a second pair of manifold valves which are connected to two of said frontwardly facing inlets, and a pair of chamber ball valves connected to a third pair of manifold valves which are connected to another two of said frontwardly facing inlets.
26. The system according to claim 1 wherein said manifold includes six inlets, at least one of which is downwardly facing and at least one of which is frontwardly facing.
27. The system according to claim 1 wherein said components include different types of components and wherein two sets of each different type of component are connected to said manifold valves.
28. The system of claim 1 wherein one of said inlets is an analyzer port.
29. The system of claim 1 further comprising a frame supporting said manifold.
30. The system of claim 29 wherein said frame includes stirrups within which said manifold is inserted.
31. The system of claim 29 wherein said frame is steel.
32. The system of claim 29 wherein said frame comprises frame elements bolted together.
33. The system of claim 29 wherein said frame includes a base.
34. The system of claim 1 further comprising a first pipe connected to said pump and to said exhaust fitting.
35. The system of claim 34 further comprising a pipe valve disposed on said pipe.
36. The system of claim 34 further comprising an oven and a second pipe, said second pipe connected to said first pipe and to said oven.
37. The system of claim 1 wherein said fluid source is a nitrogen source.
38. The system of claim 37 wherein said nitrogen source includes nitrogen ranging from 70 psig to 100 psig.
39. The system of claim 1 wherein said fluid source is an inert fluid source.
40. The system of claim 1 further comprising a flow regulator and a flow controller, wherein said fluid source is connected to said flow regulator and said flow controller is connected to said flow regulator and said opening in said capped end.
41. The system of claim 40 further comprising a fluid supply line connecting said fluid source to said flow regulator, connecting said flow regulator to said flow controller, and connecting said flow controller to said opening in said capped end.
42. The system of claim 40 wherein said flow regulator supplies fluid to said flow controller at approximately 5 psig.
43. The system of claim 1 further comprising an oven connected to said pump.
44. The system of claim 43 further comprising o-rings disposed in said oven for outgassing.
45. The system of claim 43 further comprising an oven controller.
46. The system of claim 1 further comprising a pump controller.
47. The system of claim 1 wherein said exhaust fitting is disposed proximate to said capped ends.
48. The system of claim 1 wherein said at least one opening of said semiconductor device fabrication equipment component leads to said surface for contaminant reduction.
49. The system of claim 1 wherein said surface for contaminant reduction is an internal surface.
50. An apparatus for contaminant reduction of semiconductor device fabrication equipment components, comprising:
- a manifold closed at one end and configured to accept a purge fluid at another end, a fluid passageway, a plurality of inlets, and a fluid exhaust fitting disposed downstream from said inlets, said inlets and said fluid exhaust fitting in fluid communication with said fluid passageway; and
- a plurality of manifold valves, each manifold valve being connected to one of said plurality of inlets and to each of which a semiconductor device fabrication equipment component having a surface for contaminant reduction is removably connectable, wherein said manifold valves are operable to place said removably connectable components into and out of fluid communication with said plurality of inlets.
51. The apparatus of claim 50 further comprising a plurality of caps, each of said caps removably connectable to said second end of said manifold valves and to at least one of said components.
52. The apparatus of claim 51 wherein one of said caps is connected to one end of one of said components when another end of said one of said components is connected to one of said manifold valves.
53. The apparatus of claim 51 wherein one of said caps is connected to said second end of one of said manifold valves in the absence of one of said components connected to said one of said manifold valves.
54. The apparatus of claim 51 wherein one of said caps forms a flange connection with one of said components when connected to said one of said components, and a flange connection with one of said manifold valves when connected to said second end of said one of said manifold valves.
55. The apparatus of claim 51 wherein each of said plurality of caps is connected to a cap valve.
56. The apparatus of claim 55 wherein each of said plurality of caps is connected to said cap valve via tubing.
57. The apparatus of claim 50 wherein at least one of said inlets is a downwardly facing inlet.
58. The apparatus of claim 57 wherein one of said components is a rotation assembly.
59. The apparatus of claim 58 wherein said rotation assembly is connected to one of said manifold valves with a ball joint.
60. The apparatus of claim 50 wherein at least one of said inlets is a frontwardly facing inlet.
61. The apparatus of claim 60 wherein said one of said components is a chamber ball valve.
62. The apparatus of claim 61 wherein said chamber ball valve is connected to one of said manifold valves with a flange connection.
63. The apparatus of claim 60 wherein said components include a pressure control valve.
64. The apparatus of claim 63 wherein said pressure control valve is connected to one of said manifold valves with a flange connection.
65. The apparatus of claim 50 wherein each of said semiconductor device fabrication equipment components includes an opening for connection to one of said manifold valves.
66. The apparatus of claim 65 wherein each of said semiconductor device fabrication equipment component openings leads to an inner surface for contaminant reduction, said inner surface placed into and out of fluid communication with one of said plurality of inlets.
67. A system for contaminant reduction of semiconductor device fabrication equipment components, comprising:
- a manifold having a main passageway with first and second capped ends, said first capped end configured to accept a purge fluid, a plurality of inlets disposed in between said capped ends in fluid communication with said main passageway, and an exhaust fitting disposed downstream from said plurality of inlets and being in fluid communication with said main passageway;
- a rotation assembly having a contaminated surface;
- an equipment valve having a contaminated surface and first and second openings;
- a plurality of manifold valves, one of said manifold valves having a first end connected to one of said inlets and a second end connected to said rotation assembly, and another of said manifold valves having a first end connected to another of said inlets and a second end connected to said equipment valve at said first opening;
- a cap connected to said equipment valve at said second opening;
- a purge fluid source; and
- a pump configured to be coupled to said exhaust fitting.
68. The system of claim 67 further comprising a ball joint connecting said rotation assembly to one of said manifold valves and a flange connection connecting said equipment valve to another of said manifold valves.
69. The system of claim 67 wherein said equipment valve is a chamber ball valve.
70. The system of claim 67 wherein said equipment valve is a pressure control valve.
71. The system of claim 67 wherein said system is under vacuum.
72. The system of claim 67 wherein at least one of said plurality of inlets is downwardly facing and at least one of said plurality or inlets is frontwardly facing.
73. The system of claim 72 wherein said first end of said one of said manifold valves is connected to one of said downwardly facing inlets and said first end of said another manifold valve is connected to one of said frontwardly facing inlets.
74. A system for contaminant reduction of semiconductor device fabrication equipment components, comprising:
- a manifold having a main passageway with first and second capped ends, said first capped end configured to accept a purge fluid, a plurality of inlets disposed in between said capped ends in fluid communication with said main passageway, and an exhaust fitting disposed downstream from said plurality of inlets and being in fluid communication with said main passageway;
- a plurality of means operable to place said plurality of inlets into and out of fluid communication with semiconductor device fabrication equipment components removably connectable to said manifold,
- a fluid means for providing a purge fluid to said first capped end; and
- a pressure reduction means for providing a reduced pressure within said manifold, said pressure reduction means configured to be coupled to said exhaust fitting.
75. A method for reducing contaminants of semiconductor device fabrication equipment components, each component having a contaminated surface, with a manifold having a main passageway with first and second capped ends, said first capped end configured to accept a purge fluid source, a plurality of inlets disposed in between said capped ends in fluid communication with said main passageway, and an exhaust fitting configured to accept a pump, said exhaust fitting disposed downstream from said plurality of inlets and in fluid communication with said main passageway, comprising:
- providing said manifold;
- connecting a purge fluid source to said first capped end;
- connecting a pump to said exhaust fitting;
- connecting at least one semiconductor device fabrication equipment component to at least one of said plurality of inlets;
- releasing a purge fluid into said manifold;
- placing said at least one component in fluid communication with said at least one of said plurality of inlets;
- contacting said contaminated surface of said at least one component with said purge fluid surface; and
- pumping fluid from said manifold.
76. The method of claim 75 further comprising placing said at least one component out of fluid communication with said manifold.
77. The method of claim 75 further comprising removing said at least one component from said manifold.
78. The method of claim 75 wherein the step of connecting at least one component to at least one of said plurality of inlets occurs at an opening of said at least one component.
79. The method of claim 75 wherein said surface for cleaning is an internal surface.
80. The method of claim 75 wherein contacting said contaminated surface with said purge fluid occurs under vacuum.
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Type: Grant
Filed: Mar 15, 2004
Date of Patent: May 16, 2006
Patent Publication Number: 20050199284
Assignee: Atmel Corporation (San Jose, CA)
Inventors: Darwin G. Enicks (Colorado Springs, CO), Carl E. Friedrichs (Colorado Springs, CO), Richard A. Brucher (Divide, CO)
Primary Examiner: Kevin Lee
Attorney: Schneck & Schneck
Application Number: 10/801,435
International Classification: F16K 11/00 (20060101);